I'd like to show you two common Chinese expressions of "What's your name?“ 你叫什么名字？when you talk to people at your age or younger than you. 怎么称呼您？ to people older than you.

no,it doesnt come from “你被叫什么名字”.“你被叫什么名字”is a wrong expression.“你叫什么”and“你叫什么名字”are both OK.

hmm... good question. plz remember: chinese is not a logical language. as ur example, logically, we should say: 你被叫什么名字 but we never say like this..... in chinese, there are many phenomenons like this: 被 is omitted. for example, ur bike doesn't work so u enter a repair shop and say: 我想修我的自行车。 look at this phrase, if we translate it into english, it will become: I want to repair my bike. so who gonna repair this bike? it is ME. so if this is an english repair shop, the worker think that u want to borrow some tools and repair ur bike by urself. but in china, if we enter a repair shop and say: 我想修我的自行车。 it means that i come here to find someone who can repair my bike for me. so logically, we should say: 我想让我的自行车被修。 i dont know why but we never ever say like this...